An imprint technique is a technique capable of forming a nanoscale fine pattern on a substrate and is attracting attention as one of lithography techniques for mass-producing magnetic storage media, semiconductor devices, and the like. As disclosed in Japanese Patent Laid-Open No. 2009-536591, an imprint apparatus using the imprint technique forms a pattern on the substrate by curing an imprint material (resin material) on the substrate in a state in which the imprint material and a mold on which a pattern has been formed are in contact with each other, and releasing the mold from the cured imprint material.
In the imprint apparatus, if a foreign particle is present between the mold and the substrate or the foreign particle (for example, the remaining imprint material) adheres to the mold when bringing the mold and the imprint material into contact with each other, a defect may occur in the pattern formed on the substrate. To cope with this, Japanese Patent Laid-Open No. 2011-003616 has proposed an imprint apparatus having a function of detecting such a defect in the pattern. Japanese Patent Laid-Open No. 2011-003616 has disclosed a technique of detecting the defect in the pattern based on the difference between an image obtained by capturing a pattern that has been formed on the substrate in an imprint process and a reference image prepared by capturing, in advance, a pattern (without the defect occurring) that has been formed normally on the substrate.
The technique disclosed in Japanese Patent Laid-Open No. 2011-003616 is advantageous in determining whether the defect occurs in the pattern formed on the substrate. However, the imprint apparatus requires, in order to increase its productivity, a technique for preventing the defect from occurring in the pattern formed on the substrate before it happens. Particularly, if the imprint process is continued in a state in which the foreign particle is present between the mold and the substrate or the foreign particle adheres to the mold, the foreign particle may also be sandwiched between the mold and substrate, thus damaging the mold.